Simplify the expression. $(-4k-5)(-5k+1)$
Explanation: First distribute the ${-4k-5}$ onto the ${-5k}$ and ${1}$ $ = {-5k}({-4k-5}) + {1}({-4k-5})$ Then distribute the ${-5k}.$ $ = ({-5k} \times {-4k}) + ({-5k} \times {-5}) + {1}({-4k-5})$ $ = 20k^{2} + 25k + {1}({-4k-5})$ Then distribute the ${1}$ $ = 20k^{2} + 25k + ({1} \times {-4k}) + ({1} \times {-5})$ $ = 20k^{2} + 25k - 4k - 5$ Finally, combine the $x$ terms. $ = 20k^{2} + 21k - 5$